The present disclosure relates to a treatment instrument for medical use.
A treatment instrument for medical use is known in which an insertion portion to be inserted into a body is so formed as to be curvable and a dilating body is provided at the outer circumference of this insertion portion (refer to e.g. JP-T-2012-528702).
The treatment instrument for medical use described in JP-T-2012-528702 includes an internal guide member having a shape in which the distal part is preliminarily curved, a shaft (insertion portion) that is formed into a tubular shape in which the internal guide member is provided and is so configured as to be advanceable and retractable along the internal guide member and to be curvable, and a balloon (dilating body) provided at the outer circumference of the shaft. The treatment instrument for medical use is so configured that the balloon can be inserted into a body by moving the shaft along the internal guide member.
However, in the case of related-art treatment instruments for medical use like that described in JP-T-2012-528702, the dilating body is attached to the outer circumferential surface of the insertion portion and therefore the attachment strength of the dilating body against a force in the axial direction cannot be sufficiently ensured. Thus, there is a possibility that the dilating body gets separated from the insertion portion when the dilating body is inserted into a body.